The Edoid-speaking farming peoples of the western Niger Delta, organised into some twenty-four Urhobo and nineteen Isoko clan polities - Ughelli, Agbon, Okpe, Uzere, Ozoro and the rest - each under an Ovie or a council of elders (the Okpako Orere gerontocracy), with no single Urhobo or Isoko state. The atlas draws their Itsekiri neighbours as warri_kingdom but leaves the dryland between the Ethiope and the Niger blank.
Not an ending: the Niger Coast Protectorate reached into the western delta in the 1890s and the Protectorate of Southern Nigeria took it from 1900; the Urhobo-Itsekiri rivalry over Warri then played out under British administration. Urhobo and Isoko are the largest and among the largest peoples of Delta State today.
The standard monograph on Urhobo political organisation and the Urhobo-Itsekiri contest over Warri as British rule arrived - specific to this ground.
Survey with tribal areas for the western delta peoples (Talbot's 'Sobo' = Urhobo and Isoko) - the contemporary extent source.